Nitric oxide (NO) has emerged as a key signaling molecule in plant secondary metabolite biosynthesis recently. In order to investigate the molecular basis of NO signaling in elicitor-induced secondary metabolite biosy...Nitric oxide (NO) has emerged as a key signaling molecule in plant secondary metabolite biosynthesis recently. In order to investigate the molecular basis of NO signaling in elicitor-induced secondary metabolite biosynthesis of plant cells, we determined the contents of NO, salicylic acid (SA), jasmonic acid (JA), and puerarin in Pueraria thomsonii Benth. suspension cells treated with the elicitors prepared from cell walls of Penicillium citrinum. The results showed that the fungal elicitor induced NO burst, SA accumulation and puerarin production of P. thomsonii Benth. cells. The elicitor-induced SA accumulation and puerarin production was suppressed by nitric oxide specific scavenger cPITO, indicating that NO was essential for elicitor-induced SA and puerarin biosynthesis in P. thomsonii Benth. cells. In transgenic NahG P. thomsonii Benth. cells, the fungal elicitor also induced puerarin biosynthesis, NO burst, and JA accumulation, though the SA biosynthe-sis was impaired. The elicitor-induced JA accumulation in transgenic cells was blocked by cPITO, which suggested that JA acted downstream of NO and its biosynthesis was controlled by NO. External application of NO via its donor sodium nitroprusside (SNP) enhanced puerarin biosynthesis in trans-genic NahG P. thomsonii Benth. cells, and the NO-triggered puerarin biosynthesis was suppressed by JA inhibitors IBU and NDGA, which indicated that NO induced puerarin production through a JA-dependent signal pathway in the transgenic cells. Exogenous application of SA suppressed the elicitor-induced JA biosynthesis and reversed the inhibition of IBU and NDGA on elicitor-induced pu-erarin accumulation in transgenic cells, which indicated that SA inhibited JA biosynthesis in the cells and that SA might be used as a substitute for JA to mediate the elicitor- and NO-induced puerarin biosynthesis. It was, therefore, concluded that NO might mediate the elicitor-induced puerarin bio-synthesis through SA- and JA-dependent signal pathways in wildtype P. thomsonii Benth. cells and transgenic NahG cells respectively.展开更多
Nitric oxide and reactive oxygen species are two important signal molecules that play key roles in plant defense responses. Nitric oxide generation and oxidative burst and accumulation of reactive oxygen species are t...Nitric oxide and reactive oxygen species are two important signal molecules that play key roles in plant defense responses. Nitric oxide generation and oxidative burst and accumulation of reactive oxygen species are the early reactions of Taxus chinensis suspension cells to fungal elicitor prepared from the cell walls of Penicillium citrinum. In order to investigate the relationship and/or interactions of ni- tric oxide and reactive oxygen species in the elici- tor-induced Taxol biosynthesis of T. chinensis sus- pension cells, we treated the cells with nitric oxide specific scavenger 2-4-carboxyphenyl-4,4,5,5-tetra- methylimidazoline-1-oxyl-3-oxide (cPITO), nitric ox- ide synthase inhibitor S,S′-1,3-phenylene-bis(1,2-eth- anediyl)-bis-isothiourea (PBITU), membrane NAD(P) H oxidase inhibitor diphenylene iodonium (DPI), su- peroxide dismutases (SOD) and catalase. The results show that pretreatment of T. chinensis cells with cPITO and DPI inhibited not only the elicitor-induced nitric oxide biosynthesis and oxidative burst, but also the elicitor-induced Taxol production, suggesting that both nitric oxide and reactive oxygen species are involved in elicitor-induced Taxol biosynthesis. Fur- thermore, pretreatment of the cells with cPITO and PBITU suppressed the elicitor-induced oxidative burst, indicating that the oxidative burst might be dependent on NO. Application of nitric oxide via its donor sodium nitroprusside (SNP) triggered Taxol biosynthesis of T. chinensis cells. The nitric ox-ide-induced Taxol production was suppressed by DPI, showing that the oxidative burst is involved in NO-triggered Taxol biosynthesis. However, nitric ox- ide and the fungal elicitor induced Taxol biosynthesis even though the accumulation of reactive oxygen species wass completely abolished in T. chinensis cells. Our data show that nitric oxide may mediate the elicitor-induced Taxol biosynthesis of T. chinensis suspension cells through both reactive oxygen spe- cies-dependent and -independent signal pathways. Moreover, the results of our work show that the elici- tor- and nitric oxide-induced Taxol biosynthesis is inhibited by catalase, indicating that H2O2 from the oxidative burst might be the signal molecule involved in induced Taxol production of T. chinensis cells.展开更多
为探讨真菌诱导子调控紫草素合成的分子机制,以新疆紫草无菌苗为试材,经尖孢镰刀菌、立枯丝核菌制备成的诱导子生物诱导后,对其根部进行RNA测序和分析。结果表明,与对照组比较,尖孢镰刀菌试验组差异表达基因1735个;立枯丝核菌试验组差...为探讨真菌诱导子调控紫草素合成的分子机制,以新疆紫草无菌苗为试材,经尖孢镰刀菌、立枯丝核菌制备成的诱导子生物诱导后,对其根部进行RNA测序和分析。结果表明,与对照组比较,尖孢镰刀菌试验组差异表达基因1735个;立枯丝核菌试验组差异表达基因1043个。GO(gene ontology)分析发现,2个试验组差异表达基因主要富集在细胞过程、细胞组分中膜和分子功能中催化活性等生物学过程。KEGG(kyoto encyclopedia of genes and genomes)分析发现,2个试验组在植物与病原菌互作、植物激素信号转导途径和苯丙素合成等通路均有大量差异表达基因富集。2个试验组差异表达情况相同的转录因子主要包括bHLH、AP2/ERF-ERF和LOB等,并发现参与紫草素合成及其正向调控的AeGHQH、AeDSH1、AeAP、AePAL、AeDI2、AePGT、AeHMGR、AeG10H基因在2个试验组均上调表达,其中尖孢镰刀菌试验组上调表达较显著。以上结果从分子水平探究了新疆紫草对真菌诱导子生物诱导的响应机制,为未来真菌诱导子应用于新疆紫草种植生产奠定了理论基础。展开更多
Four methods were used to prepare four crude elicitors containing different ingredients from mycelia of fungus F 5: (a) Polysaccharides A containing lipids and proteins; (b) Micromolecular polysaccharides B without li...Four methods were used to prepare four crude elicitors containing different ingredients from mycelia of fungus F 5: (a) Polysaccharides A containing lipids and proteins; (b) Micromolecular polysaccharides B without lipids and proteins; (c) Macromolecular polysaccharides F without lipids and proteins; (d) Polysaccharides H containing proteins but no lipids. The crude preparation B had the highest ability to induce taxol biosynthesis among other preparations did. The crude preparation B was through Sephadex G15 column to separate two compositions: BⅠ whose molecular weight was over 1500 D and BⅡ whose molecular weight between 700～ 1500 D. The BⅡ activity to induce taxol biosynthesis was 2.3 times higher than that of the crude preparation B, while BⅠ hadn’t the activity to induce taxol biosynthesis. By analysis of PAL activity induced by elicitors, we conclude that the changes of PAL activity could be regarded as a useful physiological indicator to select the effective elicitor.展开更多
基金supported by the National Natural Science Foundation of China(Grant No.30572331)the Natural Science Foundation of Zhejiang Province(Grant No.302785).
文摘Nitric oxide (NO) has emerged as a key signaling molecule in plant secondary metabolite biosynthesis recently. In order to investigate the molecular basis of NO signaling in elicitor-induced secondary metabolite biosynthesis of plant cells, we determined the contents of NO, salicylic acid (SA), jasmonic acid (JA), and puerarin in Pueraria thomsonii Benth. suspension cells treated with the elicitors prepared from cell walls of Penicillium citrinum. The results showed that the fungal elicitor induced NO burst, SA accumulation and puerarin production of P. thomsonii Benth. cells. The elicitor-induced SA accumulation and puerarin production was suppressed by nitric oxide specific scavenger cPITO, indicating that NO was essential for elicitor-induced SA and puerarin biosynthesis in P. thomsonii Benth. cells. In transgenic NahG P. thomsonii Benth. cells, the fungal elicitor also induced puerarin biosynthesis, NO burst, and JA accumulation, though the SA biosynthe-sis was impaired. The elicitor-induced JA accumulation in transgenic cells was blocked by cPITO, which suggested that JA acted downstream of NO and its biosynthesis was controlled by NO. External application of NO via its donor sodium nitroprusside (SNP) enhanced puerarin biosynthesis in trans-genic NahG P. thomsonii Benth. cells, and the NO-triggered puerarin biosynthesis was suppressed by JA inhibitors IBU and NDGA, which indicated that NO induced puerarin production through a JA-dependent signal pathway in the transgenic cells. Exogenous application of SA suppressed the elicitor-induced JA biosynthesis and reversed the inhibition of IBU and NDGA on elicitor-induced pu-erarin accumulation in transgenic cells, which indicated that SA inhibited JA biosynthesis in the cells and that SA might be used as a substitute for JA to mediate the elicitor- and NO-induced puerarin biosynthesis. It was, therefore, concluded that NO might mediate the elicitor-induced puerarin bio-synthesis through SA- and JA-dependent signal pathways in wildtype P. thomsonii Benth. cells and transgenic NahG cells respectively.
基金This work was supported by the Natural National Science Foundation of China （Grant No. 30572331） the Natural Science Foundation of Zhejiang Province （Grant No. 302785）.
文摘Nitric oxide and reactive oxygen species are two important signal molecules that play key roles in plant defense responses. Nitric oxide generation and oxidative burst and accumulation of reactive oxygen species are the early reactions of Taxus chinensis suspension cells to fungal elicitor prepared from the cell walls of Penicillium citrinum. In order to investigate the relationship and/or interactions of ni- tric oxide and reactive oxygen species in the elici- tor-induced Taxol biosynthesis of T. chinensis sus- pension cells, we treated the cells with nitric oxide specific scavenger 2-4-carboxyphenyl-4,4,5,5-tetra- methylimidazoline-1-oxyl-3-oxide (cPITO), nitric ox- ide synthase inhibitor S,S′-1,3-phenylene-bis(1,2-eth- anediyl)-bis-isothiourea (PBITU), membrane NAD(P) H oxidase inhibitor diphenylene iodonium (DPI), su- peroxide dismutases (SOD) and catalase. The results show that pretreatment of T. chinensis cells with cPITO and DPI inhibited not only the elicitor-induced nitric oxide biosynthesis and oxidative burst, but also the elicitor-induced Taxol production, suggesting that both nitric oxide and reactive oxygen species are involved in elicitor-induced Taxol biosynthesis. Fur- thermore, pretreatment of the cells with cPITO and PBITU suppressed the elicitor-induced oxidative burst, indicating that the oxidative burst might be dependent on NO. Application of nitric oxide via its donor sodium nitroprusside (SNP) triggered Taxol biosynthesis of T. chinensis cells. The nitric ox-ide-induced Taxol production was suppressed by DPI, showing that the oxidative burst is involved in NO-triggered Taxol biosynthesis. However, nitric ox- ide and the fungal elicitor induced Taxol biosynthesis even though the accumulation of reactive oxygen species wass completely abolished in T. chinensis cells. Our data show that nitric oxide may mediate the elicitor-induced Taxol biosynthesis of T. chinensis suspension cells through both reactive oxygen spe- cies-dependent and -independent signal pathways. Moreover, the results of our work show that the elici- tor- and nitric oxide-induced Taxol biosynthesis is inhibited by catalase, indicating that H2O2 from the oxidative burst might be the signal molecule involved in induced Taxol production of T. chinensis cells.
文摘为探讨真菌诱导子调控紫草素合成的分子机制,以新疆紫草无菌苗为试材,经尖孢镰刀菌、立枯丝核菌制备成的诱导子生物诱导后,对其根部进行RNA测序和分析。结果表明,与对照组比较,尖孢镰刀菌试验组差异表达基因1735个;立枯丝核菌试验组差异表达基因1043个。GO(gene ontology)分析发现,2个试验组差异表达基因主要富集在细胞过程、细胞组分中膜和分子功能中催化活性等生物学过程。KEGG(kyoto encyclopedia of genes and genomes)分析发现,2个试验组在植物与病原菌互作、植物激素信号转导途径和苯丙素合成等通路均有大量差异表达基因富集。2个试验组差异表达情况相同的转录因子主要包括bHLH、AP2/ERF-ERF和LOB等,并发现参与紫草素合成及其正向调控的AeGHQH、AeDSH1、AeAP、AePAL、AeDI2、AePGT、AeHMGR、AeG10H基因在2个试验组均上调表达,其中尖孢镰刀菌试验组上调表达较显著。以上结果从分子水平探究了新疆紫草对真菌诱导子生物诱导的响应机制,为未来真菌诱导子应用于新疆紫草种植生产奠定了理论基础。
文摘Four methods were used to prepare four crude elicitors containing different ingredients from mycelia of fungus F 5: (a) Polysaccharides A containing lipids and proteins; (b) Micromolecular polysaccharides B without lipids and proteins; (c) Macromolecular polysaccharides F without lipids and proteins; (d) Polysaccharides H containing proteins but no lipids. The crude preparation B had the highest ability to induce taxol biosynthesis among other preparations did. The crude preparation B was through Sephadex G15 column to separate two compositions: BⅠ whose molecular weight was over 1500 D and BⅡ whose molecular weight between 700～ 1500 D. The BⅡ activity to induce taxol biosynthesis was 2.3 times higher than that of the crude preparation B, while BⅠ hadn’t the activity to induce taxol biosynthesis. By analysis of PAL activity induced by elicitors, we conclude that the changes of PAL activity could be regarded as a useful physiological indicator to select the effective elicitor.
